Originally Posted by salopian
John,
An oil finish is exactly that! An oil finish.
Tru-oil uses a plasticising agent as do many modern finishes.
Slacum is a Purdey tradename for a modified linseed oil finish developed by Harry Lawrence one of Purdey's employees.
CCL oil is a modified linseed oil as used in the Birmingham guntrade (W C Scott) for ages.
The Italian mass producers use varnishes, polyurethane sprayed on finishes but when they are commissioned for a 'best' oil finish, they lovingly apply linseed oil and most trade makers including H&H and Purdey use 'Trade Secrets' stock oil although I do know that many stockers still have their favourite brews.

Nobili recounts that Italian best gun makers use Tru-Oil

Dr.WtS
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